1. Field Of The Invention
The present invention deals with the field of devices particularly usable for controlling fluid flow through flexible walled tubular conduits. Such valving systems are utilized in a variety of different fields of art but are particularly usable with respect to dialysis equipment. The present invention is usable with such dialysis equipment wherein a plurality of bags, normally 5 or 6 bags of liquid, are fed into a patient over an extended period of time of perhaps 15 to 20 minutes per bag. Each of these initial bags supplying fluid for traveling through one of the tubular conduits is of identical composition. On the other hand the final bag is of a distinctly different composition and it is important that the timing between the initial 5 to 6 bags and the final bag is carefully controlled. The apparatus of the present apparatus provides a fluid flow control valving system specifically capable for usage in this regard but also being generally usable with respect to any type of fluid flow through tubular conduits.
2. Background Of The Invention
Restriction of fluid flow through tubular conduits has normally been achieved by crimping or narrowing of the tubular cross section by collapsing the external wall thereof. This collapsing can be to a complete extent to prevent any fluid flow therethrough or can be to a partial extent to merely restrict flow. The present invention is particularly usable for completely preventing flow alternatively through a first and second tubular flow conduit. Examples of prior art devices for such restrictions are shown in U.S. Pat. No. 2,167,952 patented Aug. 1, 1939 to L. Jordan on a Valve; U.S. Pat. No. 2,412,397 patented Dec. 10, 1946 to L. Harper on a Flexible Tube Pump; U.S. Pat. No. 2,660,395 patented Nov. 24, 1953 to J. Mair et al on a Compressible Tube Valve; U.S. Pat. No. 3,011,750 patented Dec. 5, 1061 to C. Johnson et al on a Pipe Squeezing Apparatus; U.S. Pat. No. 3,550,619 patented Dec. 29, 1970 to P. Halasz on a Tubing Holder; U.S. Pat. No. 3,759,483 patented Sept. 18, 1973 to T. Baxter on a Fluid Actuated Control Valve; U.S. Pat. No. 4,081,170 patented Mar. 28, 1978 to D. Doss, Jr. on a Clamp For Tubular Bodies; U.S. Pat. No. 4,239,464 patented Dec. 16, 1980 to L. Hein on a Blood Pump; U.S. Pat. No. 4,436,277 patented Mar. 13, 1984 to E. Robak et al on a Torque Pinch Valve; U.S. Pat. No. 4,439,179 patented Mar. 27, 1984 to A. Lueders et al on a Dual Tubing Clamp; U.S. Pat. No. 4,484,599 patented Nov. 27, 1984 to B. Hanover et al on a Pinch-Type Pressure-Or-Flow-Regulating Valve; U.S. Pat. No. 4,576,593 patented Mar. 18, 1986 to H. Mommer on a Dosing Device For Infusion Or Transfusion Of Fluids; U.S. Pat. No. 4,585,442 patented Apr. 29, 1986 to A. Mannes on a Miniature Intravenous Infusion Rate Controller; U.S. Pat. No. 4,616,802 patented Oct. 14, 1986 to C. Tseng et al on a Tubing Occluder; U.S. Pat. No. 4,688,753 patented Aug. 25, 1987 to Charles Tseng et al on a Tubing Occluder; and U.S. Pat. No. 4,786,028 patented Nov. 22, 1988 to B. Hammond on a Fluid Flow Control Valve.